1. Field of the Invention
The present invention relates to a power supply device for supplying electric power from an on-vehicle power source to lamps that are disposed in a vehicle such as an automobile, and particularly to a power supply device with improved mechanical and electrical reliability. In addition, the present invention relates to a vehicle lamp in which the electric power can be supplied through the power supply device with improved mechanical and electrical reliability.
2. Description of the Related Art
The vehicle lamp for automobiles and the like is constructed to be equipped with a light source and other components in a tamp housing and supply electric power from the on-vehicle power source such as an on-vehicle battery to the light source to turn on the lamp or supply electric power to the other components to drive. Therefore, the tamp housing is provided with a power supply device for establishing electrical connection with the on-vehicle power source. Conventionally, the power supply device is constructed as an electrical connecting device that has conductive contacts such as an electrical socket and an electrical connector. Japanese Patent Application Publication No. 2002-170407 (JP 2002-170407 A) discloses a structure in which a connection connector that is connected to a light source side connector establishing electrical connection with the light source in the lamp housing is disposed at a part of the lamp housing in a state where the connection connector is exposed to the outside, and a power source side connector that is connected to the on-vehicle battery is connected to the connection connector to supply electric power from the on-vehicle battery to the lamp.
In the power supply device having a connector structure as disclosed in JP 2002-170407 A, because a conductive contact made of metals or the like for establishing electrical connection between the lamp side and the power source side is exposed to the outside of the lamp housing, faulty electrical connection tends to occur from corrosion or deterioration of the conductive contact and also from deformation thereof by external forces, which reduces electrical and mechanical reliability of the power supply device. In addition, in order to construct such a type of the power supply device, an opening through which the conductive contact is inserted is required to be provided in the lamp housing, and therefore the lamp housing is required to have waterproof measure and dust protection, which makes the structure of the lamp complicated. This impairs the achievement of reduction in size and cost.